Among the conventionally-known working machines are ones which include a gas engine mounted on the machine body, a cassette gas canister storing therein liquid fuel gas to be supplied to the gas engine, and a vaporizer device for vaporizing the liquid fuel gas led out from the cassette gas canister. One example of such working machines is disclosed in Japanese Patent Application Laid-Open Publication No. HEI-6-66207 (JP 06-066207 A).
In the gas-engine-mounted working machine disclosed in JP 06-066207 A, the vaporizer device is mounted on a cylinder of the engine so that the liquid fuel gas, led out from the canister, can be vaporized by the vaporizer device using heat of the cylinder.
However, with the vaporizer device in the disclosed gas-engine-mounted working machine, which uses only the heat of the engine cylinder, it is difficult to effectively accumulate sufficient heat for vaporizing the liquid fuel gas, and thus, an improvement has to be made to enhance the liquid-fuel-gas vaporizing performance.